Clinton Anthony John Duffy

Clinton Anthony John Duffy
New Zealand Department of Conservation · Marine Species Team, Biodiversity Unit

MSc Zoology
Protected fishes and marine reptiles. Marine Associate Auckland Museum - elasmobranchs.

About

105
Publications
35,701
Reads
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2,465
Citations
Additional affiliations
November 2019 - present
New Zealand Department of Conservation
Position
  • Consultant
Description
  • Technical advice on protected marine fishes and reptiles; chondrichthyan biology, ecology and conservation; marine protected areas; coastal ecology; technical support lead for protected species work-stream Hauraki Gulf Marine Spatial Plan.
July 2010 - June 2012
New Zealand Department of Conservation
Position
  • Scientific Officer (Marine)
July 2008 - June 2010
New Zealand Department of Conservation
Position
  • Scientific Officer (Marine Species - Fish)
Education
December 2009 - November 2015
University of Auckland
Field of study
  • Spatial ecology of great white sharks

Publications

Publications (105)
Article
Full-text available
106,107 ✉ replying to A. V. Harry & J. M. Braccini Nature https://doi.org/10.1038/s41586-021-03463-w (2021) Our global analysis 1 estimated the overlap and fishing exposure risk (FEI) using the space use of satellite-tracked sharks and longline fishing effort monitored by the automatic identification system (AIS). In the accompanying Comment, Harry...
Article
This article is a response to Murua et al.'s Matters Arising article in Nature, "Shark mortality cannot be assessed by fishery overlap alone," which arose from arising from N. Queiroz et al. Nature https://doi.org/10.1038/s41586-019-1444-4 (2019).
Article
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Aim Despite the unprecedented rate of species redistribution during the Anthropocene, there are few monitoring programmes at the appropriate spatial and temporal scale to detect distributional change of marine species and to infer climate‐ versus human‐mediated drivers of change. Here, we present an approach that combines citizen science with exper...
Article
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Cosmopolitan marine pelagic species display variable patterns of population connectivity among the world’s major oceans. While this information is crucial for informing management, information is lacking for many ecologically important species, including apex predators. In this study we examine patterns of genetic structure in the broadnose sevengi...
Article
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Basking sharks (Cetorhinus maximus) were widely reported throughout New Zealand waters. Once commonly observed, and sometimes in large numbers, basking sharks are now infrequently reported. Basking shark observations are known to be highly variable across years, and their distribution and occurrence have been shown to be influenced by environmental...
Article
Risks to deepwater chondrichthyans (sharks, rays, and chimaeras) from fishing are poorly understood, particularly in areas beyond national jurisdiction. We adapted productivity-susceptibility analysis (PSA) and sustainability assessment for fishing effects (SAFE) to assess the vulnerability of 173 deepwater chondrichthyans to various demersal fishi...
Article
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There remain parts of our planet that are seldom visited by humans, let alone scientists. In such locations, crowd-sourced or citizen scientist data can be critical in describing biodiversity and detecting change. Rangitāhua, the Kermadec Islands, are 750 km from the nearest human-habitation. Although our knowledge of this near pristine location ha...
Article
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Migratory movements in response to seasonal resources often influence population structure and dynamics. Yet in mobile marine predators, population genetic consequences of such repetitious behaviour remain inaccessible without comprehensive sampling strategies. Temporal genetic sampling of seasonally recurring aggregations of planktivorous basking...
Article
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Effective ocean management and conservation of highly migratory species depends on resolving overlap between animal movements and distributions and fishing effort. Yet, this information is lacking at a global scale. Here we show, using a big-data approach combining satellite-tracked movements of pelagic sharks and global fishing fleets, that 24% of...
Article
• The national extinction risk of 103 New Zealand chondrichthyans (sharks, rays, and chimaeras), ~10% of the global chondrichthyan fauna, was evaluated for the first time using the International Union for Conservation of Nature Red List of Threatened Species Categories and Criteria. Across 32 families, 103 species were assessed. • New Zealand holds...
Article
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Many shark species are at risk of overexploitation due to their high economic value, slow maturation, and low recruitment compared to most teleosts. However, there is insufficient knowledge about population structure at different spatial scales necessary to optimise fisheries models. We used single-nucleotide polymorphisms (SNPs) obtained through c...
Article
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Pelagic sharks are vulnerable to overfishing because of their low reproductive rates, generally low growth rates, and high catch rates in tuna and billfish fisheries worldwide. Pelagic sharks often migrate long distances, but they may also occur close to shore, making it difficult to classify their behaviour on the continuum from oceanic nomad to c...
Article
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White sharks, Carcharodon carcharias, are often described as elusive, with little information available due to the logistical difficulties of studying large marine predators that make long-distance migrations across ocean basins. Increased understanding of aggregation patterns, combined with recent advances in technology have, however, facilitated...
Article
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In this paper we combine analyses of satellite telemetry and molecular data to investigate spatial connectivity and genetic structure among populations of shortfin mako (Isurus oxyrinchus) in and around Australian waters, where this species is taken in recreational and commercial fisheries. Mitochondrial DNA data suggest matrilineal substructure ac...
Article
A population of the kelp Ecklonia radiata (Laminariales) has been found in mesophotic conditions at c. 72–80 m depth on the shelf surrounding Macauley Island, Rangitahua, Kermadec Islands (30 13.3'S, 178 23.8'W), in northern New Zealand, c. 900 km northeast of New Zealand on the western margin of the South Pacific Subtropical Gyre. This species was...
Technical Report
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The conservation status of all known New Zealand chondrichthyan taxa (chimaeras, sharks and rays) was reassessed using the New Zealand Threat Classification System (NZTCS). Since the last assessment (in 2005), 9 new taxa have been added to the list, 6 have been removed from it and 30 have had name changes. Also, 1 previously Data Deficient taxon is...
Technical Report
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New Zealand adopted a revised National Plan of Action for the Conservation and Management of Sharks (NPOA-Sharks 2013) in January 2014. Amongst other objectives, the NPOA-Sharks established a risk-based approach to prioritising management actions. An initial qualitative (level 1) risk assessment (RA) workshop in November 2014 assessed the risk to a...
Article
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Conservation concerns exist for many sharks but robust estimates of abundance are often lacking. Improving population status is a performance measure for species under conservation or recovery plans, yet the lack of data permitting estimation of population size means the efficacy of management actions can be difficult to assess, and achieving the g...
Article
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The application of genome-wide cytonuclear molecular data to identify management and adaptive units at various spatiotemporal levels is particularly important for overharvested large predatory organisms, often characterized by smaller, localized populations. Despite being “near threatened”, current understanding of habitat use and population struct...
Article
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The application of genome-wide cytonuclear molecular data to identify management and adaptive units at various spatio-temporal levels is particularly important for overharvested large predatory organisms, often characterized by smaller, localized populations. Despite being "near threatened", current understanding of habitat use and population struc...
Article
Courtship behaviour of the giant devil ray Mobula mobular is described from northern New Zealand, temperate southwest Pacific Ocean, for the first time. A mating train consisting of a full term pregnant female and up to four males was observed over a period of 147 minutes. Their behaviour was similar to courtship behaviour observed in other large m...
Article
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The conservation and protection of marine megafauna require robust knowledge of where and when animals are located. Yet, our ability to predict animal distributions in space and time remains limited due to difficulties associated with studying elusive animals with large home ranges. The widespread deployment of satellite telemetry technology create...
Article
The occurrence of the bignose shark Carcharhinus altimus at Ducie Island, Pitcairn Islands is reported for the first time based upon re-identification of four museum voucher specimens. The presence of a pregnant female and a juvenile confirms C. altimus breeds at Ducie Island and should be considered resident there. The specimens had been misidenti...
Technical Report
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This paper provides a characterisation of the catch of chondrichthyans in New Zealand bottom fisheries in the SPRFMO Area and information on potential risks to deepwater chondrichthyan species from SPRFMO bottom fishing. Chondrichthyans, particularly those which predominantly occur or complete most of their lifecycle below 200 m depth, are known to...
Article
Four observations of what was probably a single vagrant adult female whitetip reef shark Triaenodon obesus were made at Raoul and Meyer Islands, Kermadec Islands, New Zealand, over a 12 month period in 2014/15. This is the most southerly occurrence of the whitetip reef shark and ambient winter temperatures were close to the assumed thermal minimum...
Article
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Several international agreements and conventions require nations to establish Marine Protected Area (MPA) networks as an approach to alleviating biodiversity declines; however, a common problem in planning MPA networks is how to balance conservation objectives against economic objectives. Here, using the distributions of 102 biodiversity features a...
Article
We use a genomic sampling of both nuclear and mitochondrial DNA markers to examine a pattern of genetic admixture between Carcharhinus galapagensis (Galapagos sharks) and Carcharhinus obscurus (dusky sharks), two well-known and closely related sharks that have been recognized as valid species for more than 100 years. We describe widespread mitochon...
Technical Report
Full-text available
Biodiversity of the Kermadec Islands and offshore waters of the Kermadec Ridge: report of a coastal, marine mammal and deep-sea survey (TAN1612) New Zealand Aquatic Environment and Biodiversity Report No. 179 Clark, M.R.; Trnski, T.; Constantine, R.; Aguirre, J.D.; Barker, J.; Betty, E.; Bowden, D.A.; Connell, A.; Duffy, C.; George, S.; Hannam, S.;...
Article
The alpha taxonomy of the globally distributed shark genus Squalus has been under intense investigation recently, and many new species have been described over the last decade. However, taxonomic uncertainty remains about several taxa. Without consistent nomenclature and the ability to reliably distinguish between the different Squalus species, bas...
Article
The alpha taxonomy of the globally distributed shark genus Squalus has been under intense investigation recently, and many new species have been described over the last decade. However, taxonomic uncertainty remains about several taxa. Without consistent nomenclature and the ability to reliably distinguish between the different Squalus species, bas...
Article
Background Although widespread and intensively studied in the Southwest and Northeast Pacific Ocean, relatively little is known of the distribution and biology of the white shark (Carcharodon carcharias) Northwest Pacific. Results and conclusions Three underwater photographs of a large white shark taken near the St. Joseph oil field, Sabah, in 1981...
Article
The occurrence of the sandbar shark Carcharhinus plumbeus at Norfolk Island is confirmed. Carcharhinus plumbeus occurs over the mid to outer insular shelf from 38 m to at least 53 m depth, and appears to be at least as abundant as C. galapagensis in this habitat. No C. plumbeus were caught from shore despite most fishing effort being land-based. Th...
Article
Although primarily a coral reef species the grey reef shark Carcharhinus amblyrhynchos has been recorded from a number of subtropical oceanic islands and reefs in the Southwest Pacific Ocean. Examination of all nominal C. amblyrhynchos voucher material collected from Lord Howe Island, Elizabeth and Middleton Reefs and Norfolk Island resulted in the...
Article
The sicklefin devilray Mobula tarapacana (Philippi, 1892) is one of the largest and least known mobulids (Compagno & Last 1999; Couturier et al. 2012). Collections, fisheries bycatch data and visual records suggest it is primarily oceanic, with a circumglobal tropical and warm temperate distribution (Notarbartolo-di-Sciara 1987; Compagno & Last 199...
Research
Full-text available
Report to the New Zealand Department of Conservation on algal, marine invertebrate and fish collections made in the Kermadec Islands Marine Reserve during November 2004.
Article
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Marine mammals were observed on 46 occasions during two expeditions to the Kermadec Islands in 2004 and 2011. Species richness was greatest over the upper slope of the Bay of Plenty in May 2011, whereas abundance was greatest at the Kermadec Islands in November 2004. Diversity of cetaceans at the Kermadec Islands appears to be low however a systema...
Article
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Predation by yellowtail kingfish (Seriola lalandi) on a variety of seabirds is reported for the first time. These observations and a review of the available information indicate that at least eight species of seabird are taken by hapuku (Polyprion oxygeneios), snapper (Pagrus auratus) and yellowtail kingfish in New Zealand waters. Although predatio...
Article
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At least 2086 species from 729 families are reported from the insular shelf and upper slope of the Kermadec Islands Marine Reserve and north Kermadec Ridge. The best known groups are benthic Foraminifera, benthic macroalgae, Cnidaria, Mollusca, Crustacea, Bryozoa, Echinodermata, fishes and sea birds. However knowledge of the region’s biota remains...
Article
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The Kermadec Islands coastal fish fauna is still incompletely known, and recent expeditions there have added new fish records, and improved our understanding of its diversity and composition. This study documents 18 new fish records, presents an updated checklist of coastal fishes, and analyses the species biodiversity and biogeography. The coastal...
Article
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Five visits to the Kermadec Islands between 2004 and 2013 have increased the number of confirmed fish species from the region. The most intensive survey of shore fishes from all island groups of the Kermadec Islands was undertaken in May 2011. Additional fishes were recorded during surveys undertaken in 2004, 2012 and 2013. The main method used was...
Article
Underpinning conservation and management strategies at large spatial scales is the concept that spatial patterns of biodiversity are known, although this information is frequently lacking. Many countries routinely collect data on fish occurrence as part of stock assessments, and it has been suggested that this data could be a surrogate for other co...
Article
Subadult and adult white sharks aggregate seasonally near pinniped colonies in several parts of the globe. The time spent there may represent the most vulnerable part of their otherwise migratory life cycle. White sharks have low productivity and may suffer population declines even when afforded legislative protection. White sharks were protected i...
Article
This study assessed the levels of relatedness of Galeorhinus galeus of progeny arrays using six microsatellite DNA markers. A parentage analysis from five families (mother and litter) from the North Island of New Zealand suggested the occurrence of genetic polyandry in G. galeus with two of the five litters showing multiple sires involved in the pr...
Article
Full-text available
Statistical models of the distribution and abundance of 72 species of rocky reef fishes were developed using boosted regression trees and a set of environmental, geographic and dive-specific variables. The models were used to predict and map the occurrence and relative abundance of the selected species on shallow coastal reefs around New Zealand, i...